193
microaerophilic
methane bacteria (syn. methanogenic bacteria) a unique group among prokaryote
organisms because they produce methane as a major product of anaerobic
metabolism.
mica a group of platy, white-, green- or brown-colored minerals consisting of a
2: 1 layer (-7c1ay minerals) with the general formula: (K,Na,Ca)(Mg,Fe,Li,
AI)2_3 (AI,Si)401O(OH,F)2' Micas are rock-forming constituents of igneous
and metamorphic rocks.
Michaelis-Menten kinetics describe the rate of a biochemical process as a hyperbolic function of the concentration of the converted component. Originally
derived from a mechanistic analysis of enzyme-catalyzed reactions by
L. Michaelis and M.M.L. Menten in 19l3: V= V max S I(Km+S), where Vis the
actual rate at which the reaction proceeds, V max is the maximum rate, S is the
concentration of the converted component (often referred to as: substrate
concentration) and Km is a half saturation constant numerically equal to S at
0.5 V max' Not only applied for enzyme kinetics but also for nutrient-uptake
kinetics. At low concentrations the rate of the reaction is determined by the
initial slope of the Michaelis-Menten curve. This slope, as S approaches zero,
becomes equal to V max I Km' This ratio can be used to calculate the affinity of
an enzyme for its substrate. In the application to the kinetics of microbial
growth the equation is generally referred to as the Monod equation. With
regard to microbial growth, the equation is written: fl= flmax SI(S+K s ) where
the specific growth rate (fl) is a function of the concentration of the growth
rate-limiting substrate S, the maximum specific growth rate flmax which is
observed when S becomes saturating, and Ks (half saturation constant for
growth). The ratio flmaxlKs is a measure of the competitive ability of a
microorganism under conditions at which it has to compete for a limiting substrate at concentrations much lower than Ks.
Michael Sars Expedition (1910) in the North Atlantic, the Norwegians had already
used the Michael Sars since 1900 for extensive oceanographical and fishery
research in the Norwegian Sea. John Murray proposed to pay all expenses
privately if the Norwegian government would lend the ship and its scientific staff for a four month's summer cruise. The scientific staff consisted of i.a.
J. Murray, H.H. Gran, B. Helland-Hansen and Johan Hjort. Following
Lohmann's suggestions (-7Plankton Expedition) for the first time a motor-driven centrifuge was used to collect the nanoplankton, which passes plankton
nets. Murray and Hjort's The Depths of the Ocean gives a general account of
the expedition as well as an excellent overview of the knowledge of the
oceans up to 1912.
microaerophilic requiring oxygen at very low concentrations.
microaerophilic
methane bacteria (syn. methanogenic bacteria) a unique group among prokaryote
organisms because they produce methane as a major product of anaerobic
metabolism.
mica a group of platy, white-, green- or brown-colored minerals consisting of a
2: 1 layer (-7c1ay minerals) with the general formula: (K,Na,Ca)(Mg,Fe,Li,
AI)2_3 (AI,Si)401O(OH,F)2' Micas are rock-forming constituents of igneous
and metamorphic rocks.
Michaelis-Menten kinetics describe the rate of a biochemical process as a hyperbolic function of the concentration of the converted component. Originally
derived from a mechanistic analysis of enzyme-catalyzed reactions by
L. Michaelis and M.M.L. Menten in 19l3: V= V max S I(Km+S), where Vis the
actual rate at which the reaction proceeds, V max is the maximum rate, S is the
concentration of the converted component (often referred to as: substrate
concentration) and Km is a half saturation constant numerically equal to S at
0.5 V max' Not only applied for enzyme kinetics but also for nutrient-uptake
kinetics. At low concentrations the rate of the reaction is determined by the
initial slope of the Michaelis-Menten curve. This slope, as S approaches zero,
becomes equal to V max I Km' This ratio can be used to calculate the affinity of
an enzyme for its substrate. In the application to the kinetics of microbial
growth the equation is generally referred to as the Monod equation. With
regard to microbial growth, the equation is written: fl= flmax SI(S+K s ) where
the specific growth rate (fl) is a function of the concentration of the growth
rate-limiting substrate S, the maximum specific growth rate flmax which is
observed when S becomes saturating, and Ks (half saturation constant for
growth). The ratio flmaxlKs is a measure of the competitive ability of a
microorganism under conditions at which it has to compete for a limiting substrate at concentrations much lower than Ks.
Michael Sars Expedition (1910) in the North Atlantic, the Norwegians had already
used the Michael Sars since 1900 for extensive oceanographical and fishery
research in the Norwegian Sea. John Murray proposed to pay all expenses
privately if the Norwegian government would lend the ship and its scientific staff for a four month's summer cruise. The scientific staff consisted of i.a.
J. Murray, H.H. Gran, B. Helland-Hansen and Johan Hjort. Following
Lohmann's suggestions (-7Plankton Expedition) for the first time a motor-driven centrifuge was used to collect the nanoplankton, which passes plankton
nets. Murray and Hjort's The Depths of the Ocean gives a general account of
the expedition as well as an excellent overview of the knowledge of the
oceans up to 1912.
microaerophilic requiring oxygen at very low concentrations.